Today's networks have not only grown in size but have also expanded in their flexibility to allow various computing devices to be connected over a network. These devices provide services that are accessible from any number of locations.
At the same time, a new set of applications in the area of data centers and cloud computing are pushing the requirements of dynamic provisioning and dynamic instantiation of the network infrastructure. In many current server clusters, the physical resources to support (e.g., run) virtual infrastructure components had to be provisioned before the virtual infrastructure was needed. That is, there was no dynamic provisioning. These newer requirements of dynamic provisioning and dynamic instantiation of the network infrastructure are rapidly expanding in other segments of the information technology (IT) infrastructures where networking applies.
In traditional computer networks, data paths are implemented by interconnecting switches, routers, and other network devices throughout the network. Traditional computer networks can be too rigid and complex for these new environment requirements.
Recently, the IT industry is undergoing a revolution in the area of virtualization for the benefit of automation, flexibility and cost reduction. A typical data center network deployment scenario includes a number of virtual machines that run on servers. Each of these virtual machines may have one or more connections with other devices in the network. One problem with current virtual infrastructures is that changes made to such virtual network infrastructure by network administrators cannot be made without physically modifying physical network devices of the physical infrastructure. In such a case, the network operator may not be able to make their desired changes if they are not in control of the physical network devices that make up the physical infrastructure. Also, such changes to the physical infrastructure may causes faults or failures that impact other tenants and/or applications. In other words, there is no isolation between the changes made to the virtual infrastructure and the physical infrastructure.